Computor for ordnance data



Search Roof? Nov. 4, 194 7.

R. E. CROOKE ET AL COMPUTOR FOR ORDNANCE DATA Filed Sept. 14, 1945 3ZorSufima 2255;

" IN VENTOR RAYM0-0ECR00KE ATTORNEY WILLARD B. CONSTANTINIDES V 3 Mm$8225.23

mm Em ow Patented Nov. 4, 1947 Search Room COMPUTOR FOR ORDNANCE DATARaymond E. Crooke and Willard B. Constantinides, Great Neck, N. Y.,assignors to Ford Instrument Company, Inc., Long Island City, N. Y., acorporation of New York Application September 14, 1945, Serial No.616,230

7 Claims.

This invention relates to automatic computing mechanism for fire-controlpurposes and has for an object to provide a device of the above typehaving novel and improved operating characteristics.

A feature of the invention is the provision of computing mechanismincluding rotatable shafts which are driven at controlled ratesproportional to the computed data. Sine and cosine functions areintroduced by trigonometric integrators of the driven ball type and therates of the output shafts are measured by mechanical tachometers of theintegrator type. A motor provides the power for driving the rotatingshafts and the various integrators.

Although the novel features which are believed to be characteristic ofthis invention are pointed out more particularly in the claims appendedhereto, the nature of the invention will be better understood byreferring to the following description taken in connection with theaccompanying drawing in which a specific embodiment has been set forthfor purposes of illustration.

In the drawing the figure i a, diagrammatic representation of acomputing mechanism embodying the present invention.

Referring to the drawings more in detail the invention is shown asembodied in a, computing mechanism which derives elevation and traindata from gearing actuated by an elevation rack I and a train rack |Iassociated with the gun, or which are otherwise driven so that themovements of the gearing correspond to the elevation and train movements(E9) and (By) respectively of the gun. The mechanism is designed tocompute the lateral deflection of the sight (D3) in the inclined orslant plane of the gun and the vertical deflection of the sight (Us) andto drive dials I4 and I5 which respectively indicate these deflections.The dials I4 and I5 may comprise followthe-pointer dials from which thesetting may be applied manually to the sight or they may be connected toposition the sight relative to the gun so as to maintain the computedlateral and vertical deflections automatically set on the sight.

More specifically, the elevation rack I0 drives 2 38 connected to theshaft 35 for the above purpose. The carriage 36 carries a driving roller4| which is driven through bevelled gears 42 by a shaft 43 which isdriven by bevelled gears 44 from the shaft 45 of a constant speed motor46.

The driving roller 4| of the integrator 40 drives a ball 41 which inturn drives a sine roller 48 and a cosine roller 49 at rates which aredependent upon the orientation of the axis of the driving roller 4| withrespect to the axes of the rollers 48 and 49. The sine roller 48 isconnected by shaft 50, bevelled gears 5|, shaft 52 and bevelled gears 53to drive a shaft 54 which in turn, through bevelled gears 55 and a shaft56 drives one side 51 of a differential 5B, the other side 59 of whichdrives a shaft 60 which is connected to one side 6| of a differential62.

The cosine roller 49, through bevelled gears I0, shaft II, bevelledgears 12, shaft I3 and bevelled gears 14, drives a shaft I5 which,through bevelled gears I6, shaft I1 and bevelled gear 18 drives thedriving roller I9 of a second trigonometric integrator 80. The drivinroller I9 of the integrator is mounted on a carriage 8| which ispositioned by teeth 82, pinion 83, shaft 84 and bevelled gears 85 fromthe elevation shaft 20. The driving roller I9 drives a ball 86 which inturn drives a sine roller 81. The sine roller 81 is connected by ashaft88, bevelled gears 89, shaft 90 and bevelled gears 9| to drive thecenter of a differential 92.

The elevation shaft 20 also positions the carriage of a thirdtrigonometric integrator 96 by means of bevelled gears 97, shaft 98,pinion 99 and teeth I00 on the carriage 95. The carriage 95 carries adriving roller I0| which is driven through bevelled gears I02, shaft I03 and bevelled gears I04 from the train shaft 30. The driving roller|0I drives a ball I05 which, through a cosine roller I06, shaft Ill! andbevelled gear I08 drives the center I09 of the differential 58.

The motor 46, through the shaft 45, bevelled gears H0 and shaft IIIdrives the roller II2 of a rate integrator N3 of the two ball type whichis provided with balls II4 mounted in a carriage H5 and connected todrive a disc I I6. The carriage I I 5 is positioned by a shaft I20 bymeans of a pinion I2I and rack I22. The shaft I20 is provided with anadjusting knob I23 and with a worm I26 actuating a worm gear I2! towhich is attached a dial I28.

The disc H6 is connected by teeth I30 and pinion I3I to drive a shaftI32 which is connected to bevelled gears I33, shaft I34 and pinion I35meshing with teeth I36 and I3! on the circum- 'puted from cams or othermeans.

ference of discs I38 and I39 respectively of the rate integrators I40and MI respectively. The integrator I49 is provided with balls I42 heldin a carriage I43 which is positioned by a rack I44 and pinion I45attached to a shaft I46. The shaft I46 is connected by bevelled gearsI41 to a shaft I48 which positions the vertical deflection dial I bymeans of a Worm I49 and a worm gear I58. The shaft I48 is al o connectedby bevelled gears I5I, shaft I52, slip clutch I53, shaft I54 andbevelled gears I55 to drive the center I56 of a differential I51.

One side of the differential I51 is connected by a shaft I58 to bedriven by the roller I59 of the integrator I40. The roller I59 is drivenby the balls I42. The other side of the differential I51 is connected bya shaft I6I to one side of the differential 92. The other side of thedifferential 92 is connected by a shaft I62 and bevelled gear I63 to thecenter of a differential I614, one side of which is connected by a shaftI65 and bevelled gears I66 to the elevation shaft 20. The other side ofthe differential I64 is connected by a shaft I61 and bevelled gears I68to the shaft and. worm gear I19 to drive the lateral deflection dial I4.The roller IN is connected by a shaft I80 to one side of a differentialI8 I the other side of which is connected by a shaft I 82 and bevelledgear I83 to the center of the differential 62. The other side of thedifferential 62 is connected by a shaft I84 and bevelled gears I85 tothe shaft I11.

The center of the differential I8I is connected through bevelled gearsI86, shaft I81, slip clutch I88, shaft I89 and bevelled gear I90 to theshaft I11.

The basic equations for the lateral and vertical deflections are asfollows:

Ds=T(dBsSo sin By) +701 (2) Us=T( dEs-S0 cos Bg sin Eg) +k2 in which Dsrepresents the lateral deflection of the sight in the slant plane ofelevation of the gun, T represents time of flight of the projectile, dBsrepresents rate of train of the sight in the slant plane, S0 representsspeed of the observer or own ship, Bg represents the angle of train ofthe gun in the horizontal plane, k1 is a constant representing drift, Usrepresents vertical deflection of the sight, dEs represents rate ofelevation of the sight, Eg represents elevation of the gun and k2 is aconstant representing super-elevation. The derivation of this formula isfully set forth in the co-pending application of James D.

Tear and Charles W. Buckley, Serial No. 375,426,

filed January 22, 1941.

The drift and super-elevation may be considered as constants forcomputers for use with gun of short range or these values may be com- Inthis application these values are considered as the constants kl and I02and therefore may be taken care of by the setting of the mechanicalconnections of the apparatus.

Inasmuch as the train of the gun in the slant plane represents the trainof the sight plus the lateral deflection and the elevation of the gunrepresents the elevation of the sight plus the 4 vertical deflection,the rates 173:: and dEs may be represented as follows:

(3) dBs =-dBgSdDs (4) dEs=dEgdUs Substituting (3) and (4) in (1) and (2)and omitting the constants, the equations may be written as follows:-

(5) Ds=T(cZBgSdDs-So sin By) (6) Us=T(dEgdUs-So cos Bg sin Eg)Transposing the T in each of these equations and expressing it as a ratedT, the equations become (8) UsX =dEg-dUsS0 cos Bg sin Eg Theseequations are solved by the above described apparatus in the followingmanner. The train and elevation of the gun, (By) and (Eg) respectivelyare fed into the apparatus automatically in accordance with the movementof the gun carriage by the connections to the racks II and I9respectively so that the positions of the shafts 30 and 20 represent thetrain (By) and. elevation (Eg) of the gun and the rates of movement ofshafts 3D and 29 represent the rate of train (dBg) and the rate ofelevation (dEg) respectively. The shaft 43 is driven by the motor 46 ata constant rate which may be considered to represent the speed of theship (So) carrying the apparatus. For the purpose of this descriptionthe speed is assumed to remain constant. It is apparent however, that incase the speed of the own ship is subject to variation, a correspondingadjustment will be made in the speed of the shaft 43 by changing theratio of the bevelled gears 44 or by introducing a variable ratio drivein the shaft 43, hence the shaft 43 may be considered to rotate at arate representing the speed of the ship (So) and to drive the drivingroller M of the integrator 40 at a corresponding rate.

The shaft 35 which is connected to the shaft 30 maintains a positioncorresponding to the angle of the train of the gun (By) and causes thecarriage 96 of the trigonometric integrator 40 to take a correspondingposition. The movement transferred to the roller 48 represents the sinefunction of the position of the carriage 36 and therefore the sine ofthe angle of train of the gun (Bg), hence the shafts 52 and 54 aredriven from the driving roller 4|, ball 41 and roller 48 at a rate whichrepresents So sin By and this rate is applied as an input to one side 51of the differential 58.

The roller 49 of the trigonometric integrator 40 is positioned torepresent a cosine function of the angular position of the carriage 36.Consequently the shafts 13, 15 and 11 are driven by the roller 49 at arate which represents So cos By. This rate is applied by the shaft 11 tothe driving roller 19 of the second trigonometric integrator 80. Thecarriage BI of this second integrator is positioned by the shaft 84which in turn is connected to the elevation shaft 20 and takes aposition representing gun elevation (Eg), The output of thetrigonometric integrator derived from the roller 81 accordinglyrepresents So cos Search Room By sin By and this rate is applied by theshafts 88 and 90 to the center of the differential 92.

The rate of movement of this shaft I 65 which is taken from the shaft 20represents the rate of elevation of the gun (dEg). This is applied toone side of the differential I 64. The rate of movement of the shaft I61Which is driven from the shaft I48 represent the rate of change of thevertical deflection (dUs), as will hereafter be explained.

The rate of movement of shaft I61 is applied to the other side of thedifferential I64. Hence the shaft I62 which is driven by the center ofthe differential I64 is driven at a rate corresponding to the differenceof the two inputs (dEg-dUs). This rate is applied to one side of thedifferential 92. The center of the differential 92 as previously statedis driven at a rate representing So cos Bg sin E'g. Consequently, theshaft I6I which is driven from the other side of the differential 92represents the difference between these two quantities, or (dEgdUs-Socos Bg sin Ey) which quantity represents the righthand side of theEquation 8. The integrator I40 is connected to act as a tachometer tomeasure this rate of rotation of the shaft I6 I The roller I I2 isdriven at a constant speed by the motor 46. The ball carriage in theintegrator H3 is set in accordance with the time of flight (T)corresponding to the range which is set in by knob I23. The conversionfrom range to the time of flight may be made by appropriate graduationof the dial I28. This setting of the carriage H5 is such that the speedof rotation imparted to the disc H6 represents the reciprocal of thetime of flight hence the shaft I32 and discs I38 and I39 are driven atrates expressed as The balls I42 of the integrator I40 drive the rollerI59 which in turn is connected to one side of the differential I51. Anymovement of the center of the differential due to a difference in speedsof rotation of the shafts I58 and IBI is imparted to the shafts I54,I52, I48 and I46 to change the position of the ball carriage of theintegrator I40. These shafts are connected to drive the ball carriage ina direction to increase or decrease the speed of rotation of the rollerI59 as required to bring the rotation of the shaft I 58 into synchronismwith the rotation of the shaft I6I and thereby cause the center of thedifferential I5'I to come to rest. If the position of the shaft I48 isassumed to represent the vertical defiection (Us) and the disc I38rotates at a speed representing then the speed of the roller I59represents 1 USX which corresponds to the lefthand side of Equation 8.When the shafts I58 and I6I are rotating at the same rate, theconditions of Equation 8 are fulfilled andthe position of the shaft I 48represents the vertical deflection (Us) and the rate of movement of theshaft I48 represents rate of change of vertical deflection (dUs) Thedial I5 which is driven by the shaft I48 III accordingly represents thevertical deflection (Us). This quantity may be used to manually set thesight from the gun or may be applied to a shaft for setting the sightrelative to the gun automatically as shown for example in the Chafee eta1. Patent 2,206,875, dated July 9, 1940.

The rat-e of train of the gun in the inclined or slant plane (dBgS) isequal to the rate of train of the gun in the horizontal plane (4231])time the cosine of the elevation ofrthe gun (Eg) as set forth in thefollowing equation:

(9) dBgS=dBg cos Eg The shaft I03 which is driven by the shaft 30rotates at a rate representing the rate of train of the gun (dBg). Thisrate is applied to the driving roller IOI of the trigonometricintegrator 96. The carriage of this integrator is positioned by theshaft 98 which is connected to the elevation shaft 20 and accordinglytakes the position representing the elevation of the gun (E9). The ballI05 accordingly drives the output roller I06 of the integrator 96 at arate representing dBg cos Eg which, as set forth in Equation 9represents dBgS. This rate is applied to the center of the differential58. One side of the differential 58 as above described, is driven by theshaft 56 at a rate representing So sin By. The other side of thedifferential 58 is accordingly driven at a rate representing dBgS-So sinEg and the shaft 60 applies this rate to one side of the differential62.

The position of shaft I'I'I represents lateral defiection (Ds), Hencethe rate of movement of the shaft I84 represents the rate of change oflateral deflection (dDs). This is applied to the lower part of thedifferential 62 and is subtracted from the movement imparted by theshaft 60. Hence the shaft I82 which is driven by the center of thedifferential 62 rotates at a, rate corresponding to dBgS-dDs-S0 sin Bgwhich represents the righthand side of Equation 7. The speed of rotationof this shaft I82 is measured by the integrator I4I acting as atachometer in the following manner:

The roller Ill and shaft I are driven from the disc I39 by the balls I10which are positioned by the rack I13 and shafts I15, I11, I81, and I89from the center of differential I8I. These shafts are connected to causethe balls I10 to move to a position such that the roller I'Il rotates atthe same rate as the shaft I82. This position of the balls II0 which isrepresented by the position of the shaft I'I'I represents the lateraldeflection (Ds) Sincethe disc I39 is rotated at a rate representing therate of the roller I'II may be represented as which corresponds to thelefthand side of Equation 7. When the shafts I80 and I82 are rotating atthe same rate the conditions of Equation 7 are satisfied and theposition of the shaft I'I'I represents the lateral deflection (D3) ofthe sight from the gun in the slant plane. This deflection may be setinto the sight manually or automatically as set forth in the Chafee eta1. patent above identified.

In the above described operation of integrators I48 and MI the equatedquantities are represented by the rates of rotation of the variousshafts. Hence the actual angular positions of the shafts representingthe equated quantities are unimportant and have no effect on theaccuracy of the results. The slip clutches I53 and I88 prevent the ballcarriages from overrunning their limiting positions under extremeconditions. These slip clutches do not affect the accuracy of the resultbecause as pointed out above the relative angular positions of thevarious shafts equated by differential I51 and IBI do not enter into thecomputation,

Although a specific embodiment of the invention has been shown forpurposes of illustration, it is to be understood that the invention iscapable of various uses and that changes and adaptations may be madetherein as will be readily apparent to a person skilled in the art. Theinvention is only to be limited in accordance with the scope of thefollowing claims.

What is claimed is:

1. Apparatus for calculating the vertical deflection of a sight from agun or the like, comprising an elevation input shaft settable inaccordance with the elevation of the gun (Eg), a train input shaftsettable in accordance with the train of the gun in a horizontal plane(By), a time-offlight input shaft settable in accordance with the timeof flight of the projectile (T), a rotatable shaft, means driving saidrotatable shaft at a rate representing the own ship speed (So), atrigonometric integrator having an input member driven by said rotatableshaft and having a second input member positioned by said train shaftand having means driving an output member at a rate representing So cosBy, a second trigonometric integrator having an input member driven bysaid last output member and having a second input member positioned bysaid elevation input shaft and having means driving an output member ata rate representing So cos Bg sin Eg, an output shaft positionable torepresent the computed vertical deflection of the sight (Us), adifferential having input members driven by said elevation shaft andsaid output shaft respectively, and having an output member driven at arate representing dEgdUs, a second differential having an input memberdriven by said last output member and having a second input memberdriven by the output member representing So cos Bg sin Eg and having anoutput member driven at a rate representing dEgdUsSo cos Bg sin Eg, arate integrator having a rate input member positioned by said time offlight shaft to represent time of flight (T) and having a second inputmember driven at a constant rate and having an output member driventhereby at a rate representing i dT a second rate integrator having aninput member driven by said last output member and having a rate inputmember positioned by the output shaft representing the verticaldeflection (Us) and having means driving an output member at a raterepresenting and means positioning the vertical deflection output shaftand the rate input member of said last integrator to cause said lastoutput member to be driven at a rate corresponding to the rate of theoutput member of said second differential.

2. Apparatus for calculating the lateral deflection of a sight from agun or the like, comprising an elevation input shaft settable inaccordance with the elevation of the gun (Eg), a train input shaftsettable in accordance with the train of the gun in a horizontal plane(By), a time of flight input shaft settable in accordance with the timeof flight of the projectile (T), a rotatable shaft, meansdriving saidrotatable shaft at a rate representing the own ship speed (So), atrigonometric integrator having an input member driven by said rotatableshaft and having a second input member positioned by said train shaftand having means driving an output member at a rate representing So sinB9, a rate integrator having a rate input member positioned by said timeOf flight shaft to represent time of flight (T) and having a secondinput member driven at a constant rate and having means driving anoutput member at a rate representing L dT a second trigonometricintegrator having an input member driven by the train input shaft at arate representing the rate of train of the gun (dBy) and having a secondinput member positioned in accordance with the elevation of the gun (By)and having means driving an output member at a rate representing dBg cosEg which equals the rate of train of the gun in its normal plane (dBgS),a differential having one input member driven by said last output memberand having a, second input member driven by the output member driven ata rate representing So sin Bg and having an output member driven at arate representing dBgS-So sin By, an output shaft positionable torepresent the lateral deflection of the sight (Ds), a seconddiiferential having input members driven by said last output member andby said output shaft respectively and having an output member driventhereby at a rate representing dBgSdDsSo sin By, a second rateintegrator having an input member driven by said output member and arate input member positioned by said output shaft and having meansdriving an output member at a rate representing and means positioningthe lateral deflection out-. put shaft and the rate member of saidsecond rate integrator to cause the output member of said second rateintegrator to be driven at a rate corresponding to the rate of theoutput member of said second differential.

3. Apparatus for calculating the deflection Of a sight from a gun or thelike, comprising an elevation input shaft settable in accordance withthe elevation of the gun (Eg) a train input shaft settable in accordancewith the train of the gun in a horizontal plane (By), a time of flightinput shaft settable in accordance with the time of: flight of theprojectile (T), a rotatable shaft, means driving said rotatable shaft ata rate representing the own ship speed (So), a trigonometric integratorhaving an input member driven by said rotatable shaft and having asecond in ut member positioned by said train shaft and having meansdriving output members at rates representing So sin By and So cos Bgrespectively, a second trigonometric integrator having an input memberdriven by said output member representing So cos Bg and having a secondinput member positioned by said elevation input shaft Search So cos Bysin Eg and having an output member driven at a rate representingdEg-dUsSo cos Ba sin Eg a rate integrator having a rate input memberpositioned by said time of flight haft and having a second input memberdriven at a constant rate and having means driving an output member at arate representing a second rate integrator having an input member drivenby said first rate integrator output member and having a rate inputmember positioned by the output shaft representing the verticaldeflection (Us) and having means driving an output member at a raterepresenting UsX and means positioning the vertical deflection outputshaft and the rate input member of said second rate integrator to causeits output member to be driven at a rate corresponding to the rate ofthe output member of said second differential, a third trigonometricintegrator having an input member driven by the train input shaft at arate representing the rate of train of the gun (dBg) and having a secondinput member positioned in accordance with the elevation of the gun (Eg)and having means driving an output member at a rate representing dBg cosEg which equals the rate of train of the gun in the slant plane (dBgS),a third differential having one input member driven by the output memberof said third integrator and having a second input member driven by theoutput member representing So sin By and having an output member drivenat a rate representing dByS-So sin By, a second output shaftpositionable to represent the lateral deflection of the sight (Ds) afourth differential having input members driven by the output member ofthe third differential and by said second output shaft respectively andhaving an output member driven at a rate representing dBgS-dDs-So sin Bya third rate integrator having an input member driven by said outputmember and having a rate input member positioned by said second outputshaft and having means driving an output member at a rate representingand means positioning the second output shaft and the rate member ofsaid last integrator to cause the output member of said third rateintegrator to be driven at a rate corresponding to 10 the rate of theoutput member of said fourth differential.

4. Apparatus for calculating the vertical deflection of a sight from agun or the like, comprising an elevation input shaft settable inaccordance with the elevation of the gun (Eg), a train input shaftsettable in accordance with the train of the gun in a horizontal plane(Bg),'a time of flight input shaft settable in accordance with the timeof flight of the projectile (T), a rotatable shaft, means driving saidrotatable shaft at a rate representing the own ship speed (So), atrigonometric integrator having an input member driven by said rotatableshaft and having a second input member positioned by said train shaftand having means driving an output member at a rate representing So cosBy, a second trigonometric integrator having an input member driven bysaid last output member and having a second input member positioned bysaid elevation input shaft and having means driving an output member ata rate representing S0 cos Bg sin Eg, a second rotatable shaft, meansoperable by said elevation input shaft to rotate the said secondrotatable shaft at a rate representing the rate of elevation of the gun(dEg); a shaft driven to represent the rate of change of the computedvertical deflection of the sight (dU's), a third rotatable shaft drivenat a rate which is a function of the combined rates of said secondrotatable shaft, said dUs shaft and said last out put member and whichrepresents dEgdUs--S0 cos Bg sin E9, and rate measuring means includingan output member positioned as a function of the combined rates of saidthird rotatable shaft and the setting of said time of flight shaft torepresent T (dEg-dUs-So cos Bg sin Eg) which equals the verticaldeflection of the sight from the gun.

5. Apparatus for calculating the vertical deflection of a sight from agun or the like, comprising an elevation input shaft settable inaccordance with the elevation of the gun (Eg), a train input shaftsettable in accordance with the train of the gun in a horizontal plane(By), a time of flight input shaft settable in accordance with the timeof flight of the projectile (T), a rotatable shaft, means driving saidrotatable shaft at a rate representing the speed of the own ship (So), atrigonometric integrator having an input member driven by said rotatableshaft and a second input member positioned by said train shaft andhaving means driving an output member at a rate representing So cos By,a second trigonometric integrator having an input member driven by saidlast output member and a second input member positioned by saidelevation in ut shaft and having means driving an output member at arate representing So cos By sin Eg, a second rotatable shaft, meansdriving said second rotatable shaft at a rate representing the rate ofelevation of the gun (dEg) a shaft driven to represent the rate ofchange of the computed vertical deflection of the sight (dUs), a thirdrotatable shaft driven at a rate which is a function of the rate of saidsecond rotatable shaft and of said last output member and whichrepresents dEg--dUs-So cos B g sin Eg, a fourth rotatable shaft, meansdriving said fourth rotatable shaft at a rate representing and ratemeasuring means including an output member positioned as a function ofthe combined 11 rates of said third and fourth rotatable shafts torepresent T (dEgdUs-So cos Bg sin Eg) which equals the verticaldeflection of the sight from the gun.

6. Apparatus for calculating the lateral deflection of a sight from agun or the like, comprising an elevation input shaft settable inaccordance with the elevation of the gun (Eg), a train input shaftsettable in accordance with the train of the gun in a horizontal plane(By), a time offlight input shaft settable in accordance with the timeof flight of the projectile (T), a rotatable shaft, means driving saidrotatable shaft at a rate representing the speed of the own ship (So), atrigonometric integrator having an input member driven by said rotatableshaft and a second input member positioned by said train shaft andhaving means driving an output member at a rate representing So sin By,a second trigonometric integrator having an input member driven by saidtrain input shaft and a second input member positioned by said elevationinput shaft and having means driving an output member at a raterepresenting dBg cos Eg which represents the rate of train of the gun inthe slant plane (dBgS) a second rotatable shaft driven by said dBgSoutputmember, a third rotatable shaft, differential means driving saidthird rotatable shaft at a rate which is a function of the rates of saidsecond rotatable shaft and of said So sin Bg output member which raterepresents dBgS-So sin By, a fourth rotatable shaft positionable torepresent the computed lateral deflection (Ds), a fifth rotatable shaft,differential means driving said fifth rotatable shaft at a rate which isa function of the combined rates of said third and fourth shafts whichrate represents (dBgS-dDs-So sin Bg) rate measuring means includingmeans positioning an output member as a function of the rate ofsaidfifth rotatable shaft and of the setting, of said time of flightinput shaft to represent T (dBgSdDsSo sin By) which equals the lateraldeflection of the sight (Ds), and means actuated by said last outputmemberto drive said fourth rotatable shaft at a rate representing thechange of lateral deflection.

7. Apparatus for calculating the lateral deflecof flight of theprojectile (T), a rotatable shaft, means driving said rotatable shaft ata rate representing the speed of the own ship (So), a trigonometricintegrator having an input member driven by said rotatable shaft andhaving a second input member driven by said train shaft and having meansdriving an output member at a rate representing So sin By, a secondtrigonometric integrator having an input member driven by said traininput shaft and a second input member positioned by said elevation inputshaft and having means driving an output member at a rate representingdBg cos Eg, which represents the rate of train in the slant plane(dBgS), a second rotatable shaft driven by said dBgS output member, athird rotatable shaft driven at a rate which is a function of thecombined rates of said second rotatable shaft andof said So sin Bgoutput member which rate represents dBgS-So sin By, a fourth rotatableshaft positionable to represent the computed lateral deflection (Ds) afifth rotatable shaft, differential means driving said fifth rotatableshaft at a rate which is a function of the combined rates of said thirdand fourth shafts which rate represents dBgSdDs-So sin By, a sixthrotatable shaft, means controlled by said time of flight input shaft todrive said sixth rotatable shaft at a rate representing REFERENCES CITEDThe following references are of record in the file of this patent:

V UNITED STATES PATENTS Number Name Date 1,811,688 Gray June 23, 19311,940,518 Watson et al Dec. 19, 1933 2,356,830 Crowther Aug. 29, 19442,224,182 Crooke Dec. 10, 1940

